A drug delivery device is operable to deliver a drug from a cartridge, for example via a cannula. The cartridge is located in a cartridge holder which is part of the drug delivery device. A dose setting and delivery mechanism of the drug delivery device pushes a bung in the distal direction along the inner wall of the cartridge so that a dose of drug is delivered.
If the cartridge is not connected with the dose setting and delivery mechanism or the housing of the drug delivery device, the cartridge may be axially disposable with respect to the dose setting and delivery mechanism. Even a slight mobility of the cartridge may cause underdosing or overdosing of the drug.
It is an aim of the present invention to reduce the risk of underdosing or overdosing.